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January 29th, 2013, 05:09 AM   #1
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prove inequality



satisfying :a+b+c=0 and , abc=8

prove :

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January 29th, 2013, 05:13 AM   #2
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Re: prove inequality

Without loss of generality, let a <= b <= c.
We must have a < b < 0 and so |a| < |c| and so 1/a + 1/c < 0 and hence 1/a + 1/b + 1/c < 0.
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January 29th, 2013, 05:19 AM   #3
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Re: prove inequality

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January 29th, 2013, 06:48 AM   #4
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Re: prove inequality

greg1313:
very good solution
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